Spam Filter

Clients with email services provided by PerfectWeb may be interested in understanding a little about how the spam filter works. If your email account has the spam filter turned on, your first level of spam protection is a feature called greylisting. Greylisting drastically reduces the spam messages you receive. However, you will no longer receive all the emails sent to you and it is possible you may not receive a small percentage of legitimate email.

With greylisting, when the spam filter sees an email from an email address it has never seen before, it rejects the message with an error message that tells the sending server the email server is momentarily unavailable and to try back later. Normal email from almost all personal email accounts will be resent within a few hours, possibly within minutes. When the email arrives for the second time, it is allowed through the filter and that sender will always get through from then forward. Spam email is often sent in a "send and forget" manner that does not retry when it receives the "try back later" message. Thus, the spam email is never allowed through to your mailbox.

One downside is that the first time someone emails you, that email may be delayed from a few minutes to a few hours. The other downside is that incorrectly configured email servers from legitimate email sources may not resend the message and it will never arrive. This problem is extremely rare for personal email accounts, but may affect a few automated emails such as newsletters, purchase confirmations, shipping notices, and lost password assistance emails. The majority of these messages will make it through the spam filter, but a few may not.

The spam problem seems to be growing and this new filtering method is proving very effective at stopping spam. We were initially reluctant to implement a solution that does not deliver all email to your box, but the increasing tide of spam seemed to demand it. If you suspect you are not receiving email from someone, please contact us with the email address or domain, and they will be added to the "white list" of addresses that are never filtered. For example, you might request an address like "" or, if you are not sure of the exact email, any address from a domain like "" ( is already on the white list). And you can always request the spam filter be turned off for your account.

After email makes it through the greylisting, the contents are scanned for elements that might indicate spam, and the email will be flagged as spam if appropriate. Specifically, it will have **JUNK** added to the beginning of the subject line. You may want to create a rule or filter to move the **JUNK** email to a separate spam folder.